The present invention concerns in a dual vial connecting system for temporary connection of two containers, usually a glass or plastic vial and a plastic solvent bottle, the purpose being to reconstitute a dry product, such as a lyophilisate, powder etc., contained in a glass or plastic vial with a corresponding solvent product contained in a plastic solvent bottle, the connecting system having a cylindrical closing and connecting plastic sleeve with a lower portion having inwardly directed securing means for secure connection with the neck of the glass or plastic vial, an upper portion having an internal thread for screwing connection with the plastic solvent bottle and an integrated plastic membrane being perforated by the orifice reducer of the plastic solvent bottle when screwed into the upper inner threaded portion of the closing and connecting plastic sleeve.
For reasons of stability, freshness, marketing aspects, etc., the two products are kept and stored in separate containers prior to their immediate use. During storage, the two containers are hermetically closed.